An annular pancreas is a ring of pancreatic tissue that encircles the duodenum (the first part of the small intestine, just below the stomach).

Annular pancreas is caused by malformation during the development of the pancreas, before birth. This condition may result in a narrowing of the duodenum due to squeezing by the ring of pancreas.

Complete obstruction of the duodenum is often seen in newborns with this condition. However, half of cases are not diagnosed until symptoms occur in adulthood. There are probably many cases that go undetected due to mild symptoms.

People with this condition are more like to have a peptic ulcer.

• Feeding intolerance in newborns
• Fullness after eating
• Nausea and vomiting

Signs that may indicate annular pancreas include:

• Down syndrome
• Other congenital (something you are born with) gastrointestinal problems
• Pancreatitis
• Excessive amniotic fluid during pregnancy (polyhydramnios)

Tests include:

• Abdominal ultrasound
• Abdominal x-ray
• CT scan
• Upper GI and small bowel series

Surgical bypass of the blocked part of the duodenum is the usual treatment for this disorder.

The outcome is usually good with surgery.

• Obstructive jaundice
• Pancreatitis (inflammation of the pancreas)
• Peptic ulcer
• Perforation (tearing) of the intestine due to obstruction
• Peritonitis

Call for an appointment with your health care provider if you or your child have any symptoms of annular pancreas.

Russo MA, Redel CA. Anatomy, histology, embryology, and developmental anomalies of the stomach and duodeum. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2006: chap 45.